Stable opacified liquid detergent compositions

ABSTRACT

Stable, opaque aqueous detergent compositions comprising alkali metal polyphosphate, alkylbenzene sulfonate, higher molecular weight fatty acid alkanolamide and a phosphate ester of an ethoxylated linear or branched chain aliphatic alcohol in the ranges of proportions as set forth hereafter.

United States Patent Inventor Gerhart Karg Pompton Lakes, NJ. Appl. No. 839,670 Filed July 7, 1969 Patented Nov. 30, 1971 Assignee Witco Chemical Corporation New York, N.Y.

STABLE OPACIFIED LIQUID DETERGENT COMPOSITIONS 1 Claim, No Drawings U.S. Cl 252/529, 252/89, 252/539. 252/DlG. 14,252/DIG. 17 Int. Cl C1 1d 1/34, C 1 1d 3/066 Field of Search 252/89,

[52, I37, DIG. l7,DlGr 14 [56] References Cited UNITED STATES PATENTS 3,122,508 2/1964 Grifo etal 252/137X OTHER REFERENCES General Aniline Technical Bulletinl960#7543094 Mayhew et aL- Soap & Chemical Specialties- April 1962- p. 55- 58. 93. 95

Mayhew- Soap & Chemical Specialties- May 1962- p. 80. 81, I67, I96

Primary Examiner-Leon D. Rosdol Assistant Examiner-Dennis L. Albrecht A!rorne \'Wallenstein, Spangenberg. Hattis & Strampel STABLE OPACIFIED, LIQUID DETERGENT COMPOSITIONS This invention relates to opaque, stable liquid detergent compositions.

Opacified liquid detergent compositions, as opposed to clear or light colored solutions, have been found to be commercially advantageous because of their milk-white appearance, creamy consistency and relatively higher viscosity. In order to impart these characteristics to an aqueous solution of detergent ingredients, it has heretofore been the practice, generally, to add a polymeric latex opacifier to the composition. These conventional opacifiers are generally polymers and copolymers of styrene and other'substances. Representatives of such polystyrene opacifiers are the materials described in US. Pat. Nos. 3,326,807 and 3,382,177. While these polymers contribute to opacity, they have no influence upon the detergent properties of the liquid system.

In accordance with this invention, it has been discovered that stable, opaque liquid detergent compositions can be prepared by combining, as essential ingredients, from about 1 percent to 4 percent by weight of a phosphate ester of (a) an ethoxylated linear aliphatic alcohol having from eight to 18 carbon atoms, or of (b) ari ethoxylated branched chain aliphatic alcohol having from to carbon atoms, the aforesaid alcohols being ethoxylated with from about 2 to The aforesaid phosphate esters which are used to produce the stable opacified liquid detergent compositions of the present invention have been found to be essential to produce said compositions and to enable the higher molecular weight alkanolamides to coact in the compositions to function as opacifiers. Said alkanolamides also contribute significantly their heretofore known properties of surfactancy. Broadly speaking, the quantity of phosphate ester may vary from about 1 percent to 4 percent by weight. If the concentration is increased substantially about the 4 percent level, opacity is not obtained, while use of less than about 1 percent by weight phosphate ester will generally render the composition unstable. Particularly advantageously, the liquid detergent compositions of the present invention will contain from L5 percent to 2.5 percent, on the average about 2 percent, by weight phosphate ester.

The alkylbenzene or alkyltoluene sulfonates useful in preparing the compositions of the present invention are well about 20 mols of ethylene oxide prior to being converted into their phosphate esters, from about 3 percent to 6 percent by weight of an alkylbenzene or alkyl toluene sulfonate, wherein the alkyl group contains from eight to 18 carbon atoms from about l percent to 6 percent by weight higher molecular weight fatty acid alkanolamide, from about 1 percent to 10 percent by weight alkali metal polyphosphate, and the balance water. The aforesaid compositions are characterized by excellent stability and the ingredients utilized, which react to produce opacity, are not inactive, as are the polymer or copolymer opacifiers but, instead, contribute to the desired detergent properties of the liquid detergent compositions.

The phosphate esters of the ethoxylated linear C to C aliphatic alcohols and the phosphate esters of the ethoxylated branched chain C to C aliphatic alcohols, in which said alcohols have been adducted with from about 2 to about 20, particularly from 2 to 8 mols, of ethylene oxide per mol of said alcohol prior to being converted into their phosphate esters, are well known to the art and have found widespread use in various detergent compositions and other related applications such as are disclosed in many patents, among which are US. Pat. Nos. 3,004,056; 3,042,697; 3,033,889; 3,088,917 and 3,1 12,508. The phosphate esters used in preparing the detergent compositions of the present invention are preferably prepared by reacting 1 mol of P 0 with from 2 to 4.5 mols of the ethylene oxide adducts of the linear or branched chain aliphatic alcohol at a temperature in range of up to about l00 C., most advantageously in the range of about 50 to 65 C. Such phosphating procedures are disclosed for instance, in U.S. Pat. Nos. 2,441,295; 2,676,975; 2,701,958 and 3,004,056; Chemical Industries, Oct. 1942, pp. 516-521, 557; and Organo Phosphorus Compounds, John Wiley & Sons, New York, [950, pp. 220-223. The phosphate esters are advantageously used in the form of their water-soluble salts, preferably the sodium slats and the alkanolamine salts such as the diethanolamine and triethanolamine salts.

Illustrative of the linear and branched chain aliphatic alcohols used in the production of the phosphate esters are noctyl alcohol, n-nonyl alcohol, n-decyl alcohol, n-dodecyl alcohol, n-tridecyl alcohol, n-tetradecyl alcohol, n-pentadecyl alcohol, n-hexadecyl alcohol, oleyl alcohol, n-stearyl alcohol, Oxo alcohols such as Oxo-hexadecyl alcohol and Oxo-pentadecyl alcohol (and others as shown in U.S. Pat. No. 2,965,078), 2-ethyl octanol, and branched chain dodecanols, tetradecanols, hexadecanols, and octadecanols. Of especial usefulness are the phosphate esters of the 2 to 8 mol ethylene oxide adducts of Cm to C linear aliphatic alcohols and mixtures of two or more of said alcohols, in the form of their sodium and alkanolamine salts.

known to the at and may be generally described as those containing from eight to 18 carbon atoms in the alkyl group. For economical reasons they will generally be present as the sodium salt. They may also be present as the monovalent metal, ammonium or organic amine salt. Especially suitable is sodium dodecylbenzene sulfonate. The concentration may range from 3 percent to 6 percent by weight, preferably about 4 percent to 5 percent by weight, of the liquid detergent compositron.

The higher molecular weight fatty acid alkanolamide opacifier as used herein also acts, in its known manner, as a viscosity builder and foam stabilizer. The acyl radical of the alkanolamide is selected from the class of fatty acids having 10 to 18 carbon atoms, preferably 12 to 14 carbon atoms, and the alkanol group may have up to four carbon atoms in the case of monoalkanoamine derivatives and eight carbon atoms in the case of dialkanolamine derivatives. Especially suitable are the diethanolamides of C to C fatty acids such as lauric acid diethanolamide. Also illustrative of the said alkanolaides are oleic diethanolamide, tall oil fatty acid diethanolamide, linoleic acid diethanolamide, and the corresponding fatty acid amides of glycerol monoand di-amines, diisopropanolamine, aminoethylethanolamine, dibutanolamine and diisobutanolamine. These fatty acid alkanolamides may be prepared by various well-known techniques such as by condensing equimolar quantities of fatty acid with alkanolamine, or by condensing a molar excess of alkanolamine with fatty acid, or by reacting a fatty acid ester with alkanolamine, or by oxyalkylating, such as oxyethylating, the amide of the fatty acid. In general the fatty acid alkanolamide should be employed in amounts of about 1 percent to 4 percent and preferably about 2 percent to 3 percent, by weight of the liquid detergent composition.

The alkali metal polyphosphates useful in preparing the compositions of the present invention serve primarily as builders and concentration may vary from about I to l0 percent, preferably about 6 percent, by weight of the liquid detergent composition. Illustrative polyphosphates are sodium tripolyphosphate, tetrasodium pyrophosphate, trisodium phosphate and tetrapotassium pyrophosphate, tetrapotassium pyrophosphate being preferred.

The aqueous liquid detergent compositions of the present invention are prepared simply by combining the aforementioned ingredients with water at room temperature. No particular order of addition is necessary. The fmal preferred products exhibit a viscosity of approximately centipoises, which is most advantageous from a commercial standpoint for opalescent liquids.

The following examples are illustrative of the practice of the present invention but are not to be considered as limitative of its scope. All percentages stated are by weight.

EXAMPLE I An opaque system having a viscosity of approximately I00 centipoises was prepared by combining the following:

a. Phosphate ester oflincar aliphatic alcohol (mixture of about 80% C and about C alkyl radicals) adductcd with 6 mols ofcthylene oxide per mol of alcohol (sodium salt) 2.0% b. Sodium dodecylbenzene sulfonatc 4.5% c. Lauric acid diethanolamide 2.5% d. Tclrapotassium pyrophosphatc 6.0% c. Water 850% Samples observed over a 2-week period showed no loss of stability or opacity.

EXAMPLE ll Example I was repeated except that 1.5 percent of (a), 3.3 percent of(b), 1.8 percent of (c), 4.5 percent of(d) and 89.9 percent of (e) were combined, and again a stable, opaque composition resulted.

Certain supplemental ingredients for obtaining particular properties can, of course, be added to the stable opacified liquid detergent compositions of the present invention. Those which are used must, of course, be of such character and/or employed in such amounts as not adversely to affect the stability and opacity of the liquid detergent compositions of the present invention. Illustrative supplemental ingredients are perfumes, colors, chelating agents, corrosion inhibitors, deodorants, disinfectants, and the like.

It is important to the achievement of a stable, opacified liquid detergent composition pursuant to the present invention to utilize, in the manner and in the proportions described above, phosphate esters of ethoxylated linear C to C aliphatic alcohols and/or phosphate esters of ethoxylated branched chain C to C aliphatic alcohols. US. Pat. No. 3,l22,508, referred to above, discloses detergent compositions which contain phosphate esters, which may be those which are used in accordance with the present invention or which may be phosphate esters of ethoxylated higher alkyl phenols such as phosphated ethoxylated nonyl phenol, in admixture with dodecylbenzene sulfonates, higher fatty acid alkanolamides, and alkali metal polyphosphates. The said patent has as one of its objective, however, the preparation of heavy duty detergent compositions which are clear, homogeneous liquids. While said patent discloses opaque, very viscous compositions, they involve the utilization in the detergent compositions of large proportions of such ingredients as tall oil fatty acids and mineral oil. Such latter compositions are sharply distinguished from those made in accordance with the present invention. The said patent fails to provide any guide to or teaching of the production of the stable, opacified liquid detergent compositions of the present invention. In further regard thereto, it may be noted that, while US. Pat. No. 3,122,508 makes no distinction between the various phosphate esters of nonionic ethoxylated compounds so far as their functioning in the heavy duty detergent composition of said patent is concerned, it has been found that in order to obtain the stable, opacified liquid detergent compositions of the present invention, it is necessary to employ phosphate esters of ethoxylated linear C C aliphatic alcohols and/or phosphate esters of branched chain C -C aliphatic alcohols and proportions of the various ingredients specified above. If phosphate esters of ethoxylated higher alkyl phenols are used, such as ethoxylated nonyl phenols, in proportions of about 5 percent of the detergent composition, the resulting liquid detergent compositions are unstable. This is demonstrated by the following example III which was based upon example 77 of said patent, utilizing 5 percent of a phosphate ester of a 9 mol ethylene oxide adduct of nonyl phenol as the surfactant.

EXAMPLE [I] A mixture was prepared consisting of 5 percent phosphate ester ofa 9 mol ethylene oxide adduct of nonyl phenol, 5 percent sodium dodecylbenzene sulfonate, 1 percent lauroyl diethanolamide, 10 percent sodium tripolyphosphate and the balance water. The resulting composition was unstable and immediately broke down upon standing.

What is claimed is: I l. A stable, opacified liquid detergent composition having a 

